单选题We can safely conclude that ______.Apeople in the 19th century were eager to eat sugarBif shipwrecked sailors had drunk fresh water, things would have been even worseCone or more scientists have been hired to cheat in regard to sugarDscientists can do nothing without the money subsidized secretly
单选题
We can safely conclude that ______.
A
people in the 19th century were eager to eat sugar
B
if shipwrecked sailors had drunk fresh water, things would have been even worse
C
one or more scientists have been hired to cheat in regard to sugar
D
scientists can do nothing without the money subsidized secretly
参考解析
解析：
文中倒数第二段提到“……reported to the House of Commons that a prize of twenty-five guineas had been offered to anyone who could come up with the most “satisfactory” experiments to prove that unrefined sugar was good for feeding and fattening oxen”，即那些能证明糖类有好处的人会得到奖赏，由此推断一些科学家是被收买了以证明糖类有好处，C项正确。
文中倒数第二段提到“……reported to the House of Commons that a prize of twenty-five guineas had been offered to anyone who could come up with the most “satisfactory” experiments to prove that unrefined sugar was good for feeding and fattening oxen”，即那些能证明糖类有好处的人会得到奖赏，由此推断一些科学家是被收买了以证明糖类有好处，C项正确。
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BThe world is not only hungry，it is also thirsty for water． this may seem strange to you，since nearly 75% of the earth is covered with water． But about 97% of this water is sea water．Man can only drink and use the other 3% fresh water that comes from rivers，lakes，under-ground and other places． And we cannot even use all of that，because some of this fresh water has been made dirty．At the moment，this small amount(数量) of fresh water is still enough for us． However，our need for water is getting greater and greater． Only if we take steps to solve this problem now，we can get away from a serious world water shortage later on． The people of the world cannot have an enjoyable life without enough clean water．On one hand we should stop wasting this little water of ours，on the other hand we should find ways to reuse it，but this has not been done widely．Today，in most large cities，water is used only once and it then returns to the sea or runs into underground places．lf we can make it clean again，it can be used once more just as if it were fresh from a spring．But even if large cities reuse its water，we still would not have enough in the future． Where．could we turn to next for water? To the ocean! How can we do to make use of this great a-mount of sea water? We can take the salt from the water to make it fresh．So if we take all these steps，we'll be in no danger of drying up!( )26． Why does the writer say that the world is thirsty for water?A． The amount of fresh water is really very small．B． The people of the world waste too much water．C． The people of the world have to drink a lot of water every day．D． There are too many people in the world needing water．
C“Old wives tales” are beliefs passed down from one generation to another, For Example, most of us remember our parents’ telling us to eat more of certain foods or not to do certain things. Is there any truth in these teachings? Some of them agree with present medical thinking, but others have not passed the test of time.Did your mother ever tell you to eat your carrots because they are good for your eyes? Scientists now report that eating carrots can help prevent a serious eye disease called macular degeneration. Eating just one carrot a day can reduce the possibility of getting this disease by 40%. Garlic (蒜) is good for you, too. It can kill the type of virus that causes colds.Unfortunately, not all of Mom’ s advice passed the test of medical studies, For example, generations of children have been told not to go swimming within an hour after eating. But research suggests that there is no danger in doing so. Do sweets cause tooth problems? Well, yes and no. Sticky sweets made with grains tend to cause more problems than sweets made with simple sugars.Even though science can tell us that some of our traditional beliefs don’t hold water, there is still a lot of truth in the old wives’ tales. After all, much of this knowledge has been accumulated (积累) from thousands of years of experience in family health care. We should respect this body of knowledge even as we search for clear scientific support to prove it true or false.48. Which of the following is TRUE according to the test?A. Eating garlic is good for our eyes.B. Sticky sweets are damaging to our teeth.C. Swimming after a meal is dangerous.D. Carrots prevent people from catching colds.
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共用题干Sleep DeficitJudging from recent surveys,most experts in sleep behavior agree that there is virtually an epidemic（流行病）of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr.David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit（睡眠不足）crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night."The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark."By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake up to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr.David."They think they're okay because they can get by on 6.5 hours, when they really need 7.5,8 or even more to feel ideally vigorous."Perhaps the most merciless robber of sleep,researchers say,is the complexity of the day.Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his programme.In our society,you're considered dynamic if you say you only need 5;5 hours, sleep.If you've got to get 8.5 hours,people think you lack drive and ambition.To determine the consequences of sleep deficit,researchers have put subjects through a set of psycho-logical and performance tests requiring them,for instance,to add columns of numbers or recall a passage read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr.David."Short-term memory is weakened,as arc abilities to make decisions and to concentrate."People in the 18th and 19th centuries used to sleep about 9.5 hours a night because they had______.A:no drive and ambition B:the best sleep habitsC:no electric light D:nothing to do in the evening
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共用题干Sleep DeficitJudging from recent surveys,most experts in sleep behavior agree that there is virtually an epidemic（流行病）of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr.David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit（睡眠不足）crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night."The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark."By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake up to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr.David."They think they're okay because they can get by on 6.5 hours, when they really need 7.5,8 or even more to feel ideally vigorous."Perhaps the most merciless robber of sleep,researchers say,is the complexity of the day.Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his programme.In our society,you're considered dynamic if you say you only need 5;5 hours, sleep.If you've got to get 8.5 hours,people think you lack drive and ambition.To determine the consequences of sleep deficit,researchers have put subjects through a set of psycho-logical and performance tests requiring them,for instance,to add columns of numbers or recall a passage read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr.David."Short-term memory is weakened,as arc abilities to make decisions and to concentrate."It can be inferred from this passage that one should sleep as many hours as is necessary to______.A:improve one,S memory dramaticallyB:be considered dynamic by other peopleC:maintain one's daily scheduleD:feel energetic and perform adequately
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共用题干第三篇The IcemanOn a September day in 1991,two Germans were climbing the mountains between Austria and Italy.High up on a mountain pass,they found the body of a man lying on the ice.At that height(10,499 feet,or 3,200 meters),the ice is usually permanent, but 1991 had been an especially warm year. The mountain ice had melted more than usual so the body had come to the surface.It was lying face downward. The skeleton（骨架）was in perfect condition , except for a wound in the head.There were still skin on the bones and the remains of some clothes.The hands were still holding the wooden handle of an ax and on the feet there were very simple leather and cloth boots. Nearby was a pair of gloves made of tree bark（树皮）and a holder for arrows.Who was this man? How and when had he died? Everybody had a different answer to these ques- tions.Some people thought that it was from this century,perhaps the body of a soldier who died in World War I,since several soldiers had already been found in the area.A Swiss woman believed it might be her father,who had died in those mountains twenty years before and whose body had never been found.The scientists who rushed to look at the body thought it was probably much older,maybe even a thousand years old.With modern dating techniques,the scientists soon learned that the iceman was about 5,300 years old.Born in about 3300 B.C.,he lived during the Bronze Age in Europe.At first scientists thought he was probably a hunter who had died from an accident in the high mountains.More recent evidence,however, tells a different story.A new kind of X-ray shows an arrowhead still stuck in his shoulder. It left only a tinyhole in his skin,but it caused internal damage and bleeding. He certainly died from this wound,and not from the wound on the back of his head.This means that he was probably in some kind of a battle.It might have been part of a larger war,or he might have been fighting bandits.He might even have been a bandit himself.By studying his clothes and tools,scientists have already learned a great deal from the iceman about the times he lived in.We may never know the full story of how he died,but he has given us important clues to the history of those distant times.What can be inferred from Paragraph 2?A:The iceman was struck dead from behind.B:The iceman could have died from the wound in the head.C:The iceman was killed while working.D:The iceman lived a poor life.
共用题干第三篇The IcemanOn a September day in 1991,two Germans were climbing the mountains between Austria and Italy.High up on a mountain pass,they found the body of a man lying on the ice.At that height(10,499 feet,or 3,200 meters),the ice is usually permanent, but 1991 had been an especially warm year. The mountain ice had melted more than usual so the body had come to the surface.It was lying face downward. The skeleton（骨架）was in perfect condition , except for a wound in the head.There were still skin on the bones and the remains of some clothes.The hands were still holding the wooden handle of an ax and on the feet there were very simple leather and cloth boots. Nearby was a pair of gloves made of tree bark（树皮）and a holder for arrows.Who was this man? How and when had he died? Everybody had a different answer to these ques- tions.Some people thought that it was from this century,perhaps the body of a soldier who died in World War I,since several soldiers had already been found in the area.A Swiss woman believed it might be her father,who had died in those mountains twenty years before and whose body had never been found.The scientists who rushed to look at the body thought it was probably much older,maybe even a thousand years old.With modern dating techniques,the scientists soon learned that the iceman was about 5,300 years old.Born in about 3300 B.C.,he lived during the Bronze Age in Europe.At first scientists thought he was probably a hunter who had died from an accident in the high mountains.More recent evidence,however, tells a different story.A new kind of X-ray shows an arrowhead still stuck in his shoulder. It left only a tinyhole in his skin,but it caused internal damage and bleeding. He certainly died from this wound,and not from the wound on the back of his head.This means that he was probably in some kind of a battle.It might have been part of a larger war,or he might have been fighting bandits.He might even have been a bandit himself.By studying his clothes and tools,scientists have already learned a great deal from the iceman about the times he lived in.We may never know the full story of how he died,but he has given us important clues to the history of those distant times.The word"bandits"in Paragraph 4 could be best replaced by__________.A:soldiersB:huntersC:robbersD:shooters
共用题干U. S. Scientists Confirm Water on MarsNASA scientists said that Mars was covered once by vast lakes,flowing rivers and a Va-riety of other wet environments that had the potential to support life.Laboratory tests aboard NASA's Phoenix Mars Lander have identified water in a soil sample;the lander's robotic arm delivered the sample Wednesday to an instrument that iden-tifies vapors produced by the heating of samples.“We have water,”said William Boynton of the University of Arizona,lead scientist for ,the Thermal and Evolved-Gas Analyzer,or TEGA.“This is the first time Martian water has been touched and tasted.”The robotic arm is a critical part of the Phoenix Mars mission. It is needed to trench into the icy layers of northern polar Mars and deliver samples to instruments that will analyze what Mars is made of,what its water is like,and whether it is or has ever been a possible habitat for life.The soil sample came from a trench approximately 2 inches deep.When the robotic arm first reached that depth,it hit a hard layer of frozen soil.Two attempts to deliver samples of icy soil on days when fresh material was exposed were foiled when the samples became stuck inside the scoop.Most of the material in Wednesday's sample had been exposed to the air for two days,letting some of the water in the sample vaporize away and making the soil easier to handle.“Mars is giving us some surprises,”said Phoenix principal investigator Peter Smith of the University of Arizona.“We're excited because surprises are where discoveries come from. One surprise is how the soil is behaving. The ice-rich layers stick to the scoop when poised in the sun above the deck,different from what we expected,from all the Mars simulation tes-ting we've done so far.”Since landing on May 25,Phoenix has been studying soil with a chemistry lab,TEGA, a microscope,a conductivity probe and cameras.The science team is trying to determine whether the water ice ever thaws enough to be available for biology and if carbon-containing chemicals and other raw materials for life are present.The mission is examining the sky as well as the ground. A Canadian instrument is using a laser beam to study dust and clouds overhead.“It's a 30-watt light bulb giving us a laser show on Mars,”said Victoria Hipkin of the Canadian Space Agency.A full-circle,color panorama of Phoenix's surroundings also has been completed by the spacecraft.“The details and patterns we see in the ground show an ice-dominated terrain as far as the eye can see,”said Mark Lemmon of Texas A & M University,lead scientist forPhoenix's Surface Stereo Imager camera.“They help us plan measurements we're making within reach of the robotic arm and interpret those measurements on a wider scale.”Which one of the following statements is NOT meant by the writer?A: Scientists have been trying to break the ice-rich layers of soil on Mars.B: Scientists have been surprised by how the soil on Mars behaves.C: Scientists have been trying to find out if there is life supporting material on Mars.D: Scientists have been trying to know if water ice will melt.
共用题干第二篇The IcemanOn a September day in 1991,two Germans were climbing the mountains between Austria and Italy. High up on a mountain pass,they found the body of a man lying on the ice.At that height(10,499 feet,or 3,200 meters),the ice is usually permanent,but 1991 had been an especially warm year. The mountain ice had melted more than usual and so the body had come to the surface.It was lying face downward. The skeleton（骨架）was in perfect condition , except for a wound in the head.There was still skin on the bones and the remains of some clothes.The hands were still holding the wooden handle of an ax and on the feet there were very simple leather and cloth boots.Nearby was a pair of gloves made of tree bark（树皮）and a holder for arrows.Who was the man?How and when had he died?Everybody had a different answer to these questions. Some people thought that it was from this century,perhaps the body of a soldier who died in World War Ⅰ, since several soldiers had already been found in the area.A Swiss woman believed it might be her father,who had died in those mountains twenty years before and whose body had never been found.The scientists who rushed to look at the body thought it was probably much older,maybe even a thousand years old.With modem dating techniques,the. scientists soon leamed that the iceman was about 5,300 years old. Bom in about 3300 B.C.,he lived during the Bronze Age in Europe.At first scientists thought he was proba- bly a hunter who had died in an accident in the high mountains.More recent evidence,however,tells a differ- ent story.A new kind of X-ray shows an arrowhead still stuck in his shoulder. It left only a tiny hole in his skin,but it caused internal damage and bleeding. He almost certainly died from this wound,and not from the wound on the back of his head.This means that he was probably in some kind of a battle.It might have been part of a larger war,or he might have been fighting bandits. He might even have been a bandit himself.By studying his clothes and tools,scientists have already leamed a great deal from the iceman about the times he lived in.we may never know the full story of how he died,but he has given us important clues to the history of those distant times.What can be inferred from Paragraph 2?A:The iceman was killed while working.B:The iceman could have died from the wound in the head.C:The iceman lived a poor life.D:The iceman was struck dead from behind.
The water we drink and use is running short in the world.We all have to learn how to stop wasting our limited water.One of the steps we should take is to find ways of reusing it.Experiments have already been done in this field.Today in most large cities,fresh water is used only once,then it runs into waste system.But it is possible to pipe the used water to a purifying factory.There it can be filtered and treated with chemicals so that it can be used again,just as it were fresh from a spring.But even if every large city purified and reused its water,we still would not have enough.Then we could turn to the oceans.All we’d have to do to make use of the seawater on earth is to get rid of the salt.This process is called desalinization,and it is already in use in many parts of the world.The way to stop wasting our limited water is to________.A.do experiments with waterB.purify the used water and reuse itC.use fresh water once againD.make use of seawater
单选题The sentence “But this has rarely been a one-way street.” in the last paragraph means that _____.Acontemporary art has been nourished by modern scienceBmodern science has been nourished by artCartists can become scientists and scientists can become artistsDthe impacts of modern art and science are actually mutual
问答题The approximately 65,000 images the Surveyor orbiter has beamed home in the nearly three years it has been circling Mars are full of this kind of expected hydro-scarring. But some of the pictures took scientists by surprise. The older a formation is, the more likely it is to have been distorted over the eons--smoothed by periodic windstorms or gouged by the occasional incoming meteor. However, a few of the newly discovered water channels look flesh. That discovery has lead astonished researchers to conclude that these channels may have been recently formed. Paleontologists have long assumed that if underground water was going to bubble up on Mars, it would have to be somewhere in the balmy equatorial zones, where temperatures at noon in midsummer may reach 68 degrees Fahrenheit (20 degrees Centigrade). Almost all the new channels, however, were discovered at the planet’s relative extremes--north of 30 degrees north latitude and south of 30 degrees south latitude--and all were carved on the cold, shaded sides of slopes.
单选题Countless divorced politicians would have been elected out of office years ago had they even thought of a divorce, let alone ______ one.AgettingBto getCgottenDget